Web breakage detection device, for rotary printing machine, uses displacement of guide roller bearing shell relative to carrier element upon loss of web tension

摘要

Device has a guide roller (3) around which paper web (2) is passed supported in a bearing having a bearing shell (22) which moves relative to a carrier element (25) against force of a bias spring (32) as a result of force exerted by the web, into contact with a stop (A1). Bearing shell is moved in the opposite direction by the spring bias upon loss of the web tension into contact with a second stop (A2) for operation of a switch element (15).